Verify Views files against decompiled, extract embedded types

Fixed files:
- SkiaImageButton.cs: Added SVG support with multi-path search
- SkiaNavigationPage.cs: Added LinuxApplication.IsGtkMode check
- SkiaRefreshView.cs: Added ICommand support (Command, CommandParameter)
- SkiaTemplatedView.cs: Added missing using statements

Extracted embedded types to separate files (matching decompiled pattern):
- From SkiaMenuBar.cs: MenuBarItem, MenuItem, SkiaMenuFlyout, MenuItemClickedEventArgs
- From SkiaNavigationPage.cs: NavigationEventArgs
- From SkiaTabbedPage.cs: TabItem
- From SkiaVisualStateManager.cs: SkiaVisualStateGroupList, SkiaVisualStateGroup, SkiaVisualState, SkiaVisualStateSetter
- From SkiaSwipeView.cs: SwipeItem, SwipeStartedEventArgs, SwipeEndedEventArgs
- From SkiaFlyoutPage.cs: FlyoutLayoutBehavior (already separate)
- From SkiaIndicatorView.cs: IndicatorShape (already separate)
- From SkiaBorder.cs: SkiaFrame
- From SkiaCarouselView.cs: PositionChangedEventArgs
- From SkiaCollectionView.cs: SkiaSelectionMode, ItemsLayoutOrientation
- From SkiaContentPresenter.cs: LayoutAlignment

Verified matching decompiled:
- SkiaContextMenu.cs, SkiaFlexLayout.cs, SkiaGraphicsView.cs

Build: 0 errors

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Rendering/SkiaRenderingEngine.cs

@@ -313,31 +313,3 @@ public class SkiaRenderingEngine : IDisposable
         GC.SuppressFinalize(this);
     }
 }
-
-public class ResourceCache : IDisposable
-{
-    private readonly Dictionary<string, SKTypeface> _typefaces = new();
-    private bool _disposed;
-
-    public SKTypeface GetTypeface(string fontFamily, SKFontStyle style)
-    {
-        var key = $"{fontFamily}_{style.Weight}_{style.Width}_{style.Slant}";
-        if (!_typefaces.TryGetValue(key, out var typeface))
-        {
-            typeface = SKTypeface.FromFamilyName(fontFamily, style) ?? SKTypeface.Default;
-            _typefaces[key] = typeface;
-        }
-        return typeface;
-    }
-
-    public void Clear()
-    {
-        foreach (var tf in _typefaces.Values) tf.Dispose();
-        _typefaces.Clear();
-    }
-
-    public void Dispose()
-    {
-        if (!_disposed) { Clear(); _disposed = true; }
-    }
-}